We look to the example of Jesus surrounded by the great cloud of witnesses who lived this faith before us. Jesus is the pioneer and perfecter of our faith -- he endured the cross. Notice it says he "set aside the shame". Crucifixion was considered the most shameful way to die in the first century. It was reserved for the worst kinds of criminals. The crucified were crucified naked and were often refused burial for extended times. People did not speak of those who had been crucified. Notice the radical nature of the Christian gospel: to preach Jesus Christ crucified seemed absolutely ridiculous and abject folly to the Greek speaking world. To preach Jesus Christ resurrected seemed to them to be absurd at the very best. Why speak of such things in public?
The author then enters into an extended discussion of human suffering as a form of discipline from God. Our earthy parents use various forms of discipline to for and shape and teach us about this life. Our heavenly Father uses life's experiences and hardships to form and shape us for eternity. Because of this knowledge we should "lift drooping hands and strengthen weak knees (12)." In other words the struggles you are enduring have eternal value and purpose so stand up and be strong and walk the path God has set for you.
The rest of 12 and chapter 13 are a typical end to a first century letter. It is filled with advice and admonitions. We are to "pursue peach with everyone (14)" and to approach Jesus, not with fear but with boldness (22-24). We are not shaken but are now able to stand firm and with full confidence.